Grapevine Nutrition

Question 1

How many essential nutrients do grapevines need for healthy function?

Answer 1

17

Question 2

Name the 6 Macronutrients needed for grapevine nutrition.

Answer 2

Nitrogen (N)
Phosphorus (P)
Potassium (K)
Calcium (Ca)
Magnesium (Mg)
SULFUR (S)

Question 3

Nitrogen (N)

Answer 3

Function in plant: Controls growth and development.

Symptoms of Deficiency: Low vigor and chlorosis starting in older leaves.

Symptoms of Excess: Dark green leaves and high vigor. Reduced sugar and red color accumulation in fruit.

Question 4

Phosphorus (P)

Answer 4

Function in plant: Required for energy storage and transport.

Symptoms of Deficiency: Yellow or red patches between veins on older leaves and low yields. Easily confused with leafroll or mite damage. Rare except on acidic soils.

Symptoms of Excess: Potassium, iron, and zinc deficiency.

Question 5

Potassium (K)

Answer 5

Function in plant: Regulates water movement in and out of plant cells. Important for red color development and deacidification of fruit during ripening.

Symptoms of Deficiency: Older leaves turn yellow or red at their edges. Leaves may ultimately become dark reddish-brown with green veins and curl under. Low yields and low fruit pH.

Symptoms of Excess: Elevated fruit pH. Magnesium deficiency.

Question 6

Calcium (Ca)

Answer 6

Function in plant: Component of cell walls. Maintains integrity of vine’s structure.

Symptoms of Deficiency: Rare except on acidic soils.

Question 7

Sulfur (S)

Answer 7

Function in plant: Component of proteins and vitamins.

Symptoms of Deficiency: Chlorosis. Rare since sulfur-based fungicides are used.